Imagine a restaurant where the kitchen shuts down for an hour each time the staff switches from making burgers to fries. That would be pretty frustrating for a customer—and cost the business a lot of money.
Between the 1950s and the 1970s, manufacturers faced a similar crisis—million-dollar equipment would sit idle for hours during changeovers. Shigeo Shingo, an Industrial Engineer at Toyota Motor Corporation, recognized this inefficiency and helped pioneer a solution: Single-Minute Exchange of Die (SMED).
SMED is a systematic method of lowering setup and changeover times to under 10 minutes. What began as a way to solve Toyota's efficiency problems has revolutionized manufacturing worldwide. SMED's quick changeover capabilities are just as important today when manufacturers can face downtime costs of $8,000 a minute.
In this post, we’ll explore how SMED allows manufacturers to quickly switch between processes while maintaining quality and minimizing waste. We’ll break down the SMED system and share tips for successfully implementing SMED at your facility.
Understanding the SMED process and changeover elements
"Single minute" in SMED doesn’t mean completing changeovers in 60 seconds. Instead, SMED aims to reduce changeover times to single-digit minutes (under 10 minutes). Central to this is the difference between internal and external setup elements, which determine whether—and how long—machines pause operations.
Internal setup elements
These elements are tied to the equipment’s core operations. They are called "internal" because they directly interact with the machine's components. As a result, setting them up requires stopping the machine. Examples include:
- Removing or mounting dies.
- Attaching or removing tooling.
- Making essential adjustments.
- Direct machine setup activities.
External setup elements
External elements are independent of core machine operations. These tasks involve preparation, organization, or other supporting activities that can be done regardless of the machine's current state. Examples include:
- Preparing dies or tooling.
- Transporting materials.
- Pre-heating molds.
- Gathering necessary tools and documentation.
Here's where SMED gets interesting: Factories can convert many internal setup activities to external ones. This fact might seem minor, but it can be a game-changer in achieving single-digit minutes. Instead of shutting down production to gather tools or prepare materials, workers can complete these tasks while machines keep running.
Many traditional equipment changeover processes combine internal and external elements, creating unnecessary downtime. However, by clearly separating and optimizing these elements, manufacturers can dramatically reduce machine stoppage time—even before implementing more advanced improvements.
The four-step SMED system for reducing changeover time
To achieve the best results, it's essential to follow a systematic approach. The four steps outlined below provide a structured framework for reducing changeover times.
Step 1: Separate internal and external setup elements
Start with observation. Study your current changeover process and separate external elements from internal ones. Ask yourself: Do we have to stop machines before performing this activity? Or can we do it while the machines run? Many manufacturers are surprised that many internal activities can happen during production.
Step 2: Convert internal elements to external elements
With your elements and processes clearly identified, convert as many internal activities to external as possible. For example, instead of adjusting tools during downtime, adjust them during production. That way, if there’s a breakdown, they’ll be ready.
Step 3: Streamline remaining internal elements
Now, it’s time to make the remaining internal elements as efficient as possible by identifying and eliminating bottlenecks. This step could require obtaining new equipment to help technicians work faster. For example, replace bolts with quick-release clamps or use standardized height settings instead of manual adjustments.
Step 4: Streamline all aspects of the setup operation
Here, you’ll focus on optimizing your processes as a whole. For example, you can study your schedules and make changes to ensure your team works optimally. You could also streamline your parts inventory with a Computerized Maintenance Management System (CMMS). Another strategy is to introduce Standard Operating Procedures (SOPs) that help technicians work faster.
Benefits of implementing the SMED system in manufacturing
Reduced changeover times are just the beginning. SMED creates a domino effect of benefits across operations. Here are a few:
Increased production flexibility
Faster changeovers mean you can run smaller batches profitably. Need to switch from Product A to Product B to meet a rush order? No problem. You can meet customer demand without keeping excess inventory on hand.
Lower manufacturing costs
SMED helps cut costs in multiple ways: less time spent on changeovers means lower labor costs, smaller inventories reduce storage costs, and more efficient processes reduce waste throughout production.
Improved equipment effectiveness
When machines spend less time being set up and more time running, your Overall Equipment Effectiveness (OEE) improves. You’ll see better utilization of your valuable manufacturing assets.
Effective SMED implementation strategies for changeover optimization
With proper implementation, you’ll see SMED’s benefits in your operations. Here are a few key strategies to apply:
Identify and prioritize internal elements
Start by mapping your current changeover process. Which tasks require machine stoppage? Which ones take the most time? This analysis helps you prioritize the most significant opportunities so you can start seeing improvements quickly.
Use functional clamps and quick-release mechanisms
As we mentioned earlier, optimizing your tools and parts can make a big difference. Replace time-consuming fasteners with quick-release alternatives. Instead of dealing with multiple bolts that need 20 turns each, use quarter-turn fasteners or quick clamps. These small changes add up to significant time savings.
Implement parallel operations
Instead of having one person handle the entire changeover or having your technicians work sequentially, let them work simultaneously. For example, one technician can prepare tools while another removes clamps.
Eliminate adjustments
Replace time-consuming adjustments with preset solutions. Instead of manually adjusting die heights or alignment, use standardized spacers and locating pins.
Standardize procedures
Create clear procedures that anyone can follow. Use visual guides, checklists, and standardized tools. Digital SOPs in a CMMS are a valuable tool here. Changeovers become consistent, efficient, and error-free when everyone follows the same playbook.
SMED and continuous improvement in lean manufacturing
SMED isn’t just a standalone method—it’s a cornerstone of lean manufacturing principles. It works with other lean principles to boost efficiency. For example, 5S principles—also a core element of Total Productive Maintenance—ensure tools and components are always organized and ready for quick changeovers
Most importantly, SMED embodies the continuous improvement (Kaizen) philosophy at the heart of lean manufacturing. Each reduction in changeover time contributes to higher productivity over time. A setup that takes eight minutes today might take six minutes next month through small, incremental changes.
Challenges in SMED implementation in manufacturing
Like any transformative process, SMED comes with its own set of challenges. Here are a few to look out for and some tips to handle them:
Resistance to change
In many cases, the biggest challenge isn't technical—it's human. Many experienced operators have been performing changeovers the same way for years and might wonder about the point of a new method. Overcoming this resistance requires clear communication about SMED's benefits and involving operators in the improvement process from day one.
Initial investment
While some SMED improvements are simple and low-cost, others require purchasing new equipment or modifying existing machinery. The upfront cost of modifications like quick-release clamps or automated adjustments can be a barrier for teams. That said, SMED is a long-term investment. Weigh the cost of the changes against potential downtime losses.
Training requirements
Proper training is essential to ensure employees understand and effectively implement SMED principles. Your teams might need to learn new procedures, practice parallel operations, and master standardized processes. Ensure you plan for the time and resources to make this happen effectively.
Digital solutions to enhance the SMED process
Digital tools, like a Computerized Maintenance Management System (CMMS), can significantly enhance your SMED process. A mobile-friendly CMMS empowers your team to implement SMED directly on the shop floor. Here’s how:
Real-time tracking
You can see exactly how long each element takes by using digital tools (like a CMMS with time tracking for work orders). Doing this will help you to identify bottlenecks and eliminate time wastage.
Digital guides
Teams can use digital SOPs instead of paper checklists and procedures. With MaintainX, for example, users can access step-by-step instructions, photos, voice memos, and previous changeover notes from their devices, ensuring consistent execution every time.
Equipment-monitoring
Smart sensors and IoT devices add another layer of precision to SMED. They can monitor equipment status and automatically alert teams when a changeover is coming up.
Data analysis
With the right CMMS, you can extract valuable insights from your data. MaintainX’s reporting feature, for example, provides you instant visibility into your most important metrics, such as downtime. It will enable you to identify, over time, just how well your SMED initiatives are performing. You’ll know where you need to improve and where you need to double down.
SMED and modern manufacturing: Your tool for rapid production changes
SMED isn’t just about minimizing downtime and keeping your assets online; it’s about ensuring continuous improvement. Practicing the fundamentals—from the four-step system to the implementation strategies—will set you on the path to broader lean manufacturing success. You'll be able to respond quickly to market demands, reduce waste, and improve overall efficiency. Most importantly, you’ll create a culture of excellence.
Ready to start your SMED journey? MaintainX can help digitize and streamline your changeover processes. Our CMMS provides real-time tracking, digital guides, and data analysis tools to make SMED implementation successful. Book a tour today to find out more.
FAQs on SMED
SMED is widely applicable in industries such as automotive, food and beverage, pharmaceuticals, and electronics—anywhere frequent changeovers are required.
SMED eliminates unnecessary time, labor, and resource waste by minimizing downtime and streamlining changeover processes.
The most common obstacles to successful SMED adoption include resistance to change, upfront equipment costs, and employee training.
Employee involvement is crucial. Engaging frontline workers in the process ensures better adherence to new procedures and fosters a culture of continuous improvement.
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